This disclosure is to a system and a method for separating entrained immiscible liquid components from a gas stream.
The subject of the invention generally relates to gas/liquid (2 phase) separators or gas/liquid/solid (3 phase) separators. The invention may also be practiced in which the liquid phase is a mixture of an aqueous phase and an organic or hydrocarbon phase. Separators of this type are typically process vessels that may be at atmospheric or above atmospheric pressure. The main function of the separator system of the invention is to segregate immiscible phases of a process stream. The process stream may be in the form of gas that carries with it an immiscible liquid component, frequently referred to as a “wet gas” stream. The function of the separator of this invention is to separate out the liquid component to provide at the output of the separator a “dry gas” stream, that is, a gas stream that is relatively free from entrained liquids.
The systems and methods of this disclosure are basically applicable to removing liquid dispersed in a gas stream, such as in which the liquid is of relatively little volume compared to the gas and in which the liquid may be primarily in the form of mist and removing gas from a liquid stream in which the gas may be of a relatively small proportion (by weight) of the stream. In the first instance the separation process is generally referred to as “gas demisting” and in the second instance the separation process is generally referred to as “liquid degassing”.
Separators for separating liquid components from a gas stream are commonly utilized in the oil and gas industry, specifically in oil and gas production, oil refining and gas processing, and are also used in the mining industry, chemical plants, water treatment facilities, pulp and paper plants and pharmaceutical manufacturing facilities.
Separation of immiscible components of a wet gas stream usually depends on the force of gravity. Gravity can be either natural gravity, that is, the pull of mass towards the center of the earth or created (artificial) gravitational forces such as represented by centrifugal separators. Natural gravity is usually used by flowing a stream having immiscible components into a vessel which provides a quiescent zone, that is, a relatively undisturbed environment that allows gravity to act on heavier components of the stream and move them into a downward part of the vessel. This movement has the counteraction of the lighter components of the stream migrating to an upward part of the vessel. In this way, the heavier components, that is, liquids, can be withdrawn from the lower part of the vessel and the lighter components, that is, gases, withdrawn from an upper part of the vessel.
Separators commonly have an inlet momentum absorber or deflector to reduce the momentum of the incoming stream and to distribute liquid and gas within the separator vessel. This kinetic energy reduction initiates phase separation inside a separator vessel.
Artificial gravity can be generated by the use of a vortex tube or tubes. A vortex tube is typically an elongated tube having a cylindrical interior wall that is preferably vertically mounted or at least mounted with a vertically downward tangent. The vortex tube (or each vortex tube if more than one is employed) has an inlet arranged so that wet gas flowing therein tangentially intersects the interior wall of the vortex tube and flows around the interior wall to thereby create centrifugal force that is applied to the components, the centrifugal force serving to move the heavier component, that is, the liquid component, towards the wall of the vortex tube while the lighter component (gas) is forced towards the interior of the tube. In a typical vortex tube, the gas is withdrawn from an upper central vortex opening while the liquid component is withdrawn from a liquid outlet in the bottom portion of the tube.
This invention herein is a system and method employing a separator internal process apparatus in combination with a vortex tube or a “vortex tube cluster”. In a vortex tube cluster, each tube receives an approximately equal portion of the incoming flow stream.
For additional background information relating to the general subject mater of this disclosure reference may be had to the following previously issued United States patents:
U.S. Pat. No.InventorTitle3,930,816MiczekStructure For A Gas and Liquid ContactingChamber In A Gas Effluent Processing System4,838,906KiselevContact-And-Separating Element6,576,029WestSystem For Separating An Entrained LiquidComponent From A Gas Stream6,673,135WestSystem and Method Of Separating EntrainedImmiscible Liquid Component Of An Inlet Stream6,709,500WestSystem For Separating Entrained Liquid From AGas Stream Using A Sloped Vessel7,001,448WestSystem Employing A Vortex Finder Tube ForSeparating A Liquid Component From A GasStream